INJECTION DEVICE AND ASSEMBLY METHOD

摘要

The invention refers to an injection device comprising a housing (10) containing a cartridge (20) containing a medicament and a movable bung (21), wherein the housing (10) comprises an inner thread (17), a piston rod (30) for moving the bung (21) during dose dispensing, wherein the piston rod (30) comprises an outer thread (31) engaging the inner thread (17) of the housing (10) a bearing (33) at its end facing the bung (21), and a driver (40) coupled to the piston rod (30) for driving the piston rod (30) during dose dispensing. In the unused delivery state of the device, the bearing (33) abuts the bung (21). The invention further refers to an assembly method for such an injection device.